0 0 0 0 0 0 O O O O O O 59 57 55 53 51 49 0 O 88 - pink - Published 2000 Published

cordierite 54A Gp B.G.C.M. Series - with 0 - tonalite with - O Nn garnet W

92 54B

Tn 53O

Manitoba Geological Survey Geological muscovite pegmatite;

0

O hypersthene; H U D S O N B A Y Williston Basin Churchill Province Province Superior Basin 92 KILOMETRES

calc-silicate lenses; calc-silicate

53N Gods

Kasmere Lake, NTS 64N, 1:250 000 64N, NTS Lake, Kasmere River 54C

0 53K ’ PHANEROZOIC aplite 0 PRECAMBRIAN

tourmaline; 54F ’

00 0 50 100 150 200 250 54K River O 0

00 ’ Hayes O

0

Churchill Lake

’ Gods 59 00 60

O

andalusite Lake 00

O River

53E

53L

53M 54D

54E River

54L Island 100 - foliated granite -

0 52E

100

O

52L

53D 52M 0 54M O

Gn

96

Winnipeg Churchill Nelson 96

River Minnesota

sillimanite NTS 64N River 62I 64I 63I

62P

64P 63P

63A 63H 62H

64H

64A

Nunavut

Seal Red - semipelitic paragneiss to metatexite, semipelitic with paragneiss + garnet - b - biotite gneiss, psammite b - rocks with albite-pyroxene k -

Southern

Indian S S Nj

garnet hornblende; Lake River semipelitic paragneiss to metatexitesemipelitic paragneiss Granite, massive to massive foliated,Granite, granite Hybrid bearing, Tonalite, cordierite metatexite; gneiss with arkosic derived Meta-arkose; W W gneiss biotite with psammite rocks Calc-silicate toSemipelitic metatexite, paragneiss W to quartzite quartzite Impure and pink aplite, granite Foliated hybrid alaskite with diatexite to biotite metatexite, Granodiorite (monzocharnokite) granite Hypersthene granodiorite diatexite to biotitegranodiorite metatexite; tonalite porphyritic granite porphyritic

WINNIPEG e

Thompson

LAKE

64O 64J

64G

64B 0

63O

63J O

63G

63B

62O 62J

62G

LAKE KASMERE LAKE Assiniboin 100

North Dakota

MANITOBA k x N Q 0 Sn Kb T G G

Brandon O Z

SEAL RIVER DOMAIN G Gh W W

W W Lk Hudsonian Wollaston Group

Cedar

R 100 64N n LAKE

64K a w 64F

SEAL RIVER DOMAIN Proterozoic Archean and/or Proterozoic Archean e 64C h Lake WINNIPEGOSIS 63N 63K tc 63F

Lynn Lake a 62N 63C 62K 62F

INDEX MAP AND MAJOR TECTONIC DIVISIONS k s

a

Flin Flon S 0 0 0 0 0 0 O O O O O O LEGEND 59 57 55 53 51 49 BEDROCK GEOLOGY COMPILATION MAP SERIE - with - with - with k - with k - S Nn Nh Nk W W W GEOLOGICAL DOMAINS W - granite and granite -

WOLLASTON DOMAIN - tonalite with - Gj - with calc- garnet 10 garnet; - with granite, with - Tn Nl - with amphibolite; with - Tk W - with granodiorite with - Th Tj Km0 1020304050Km pegmatite zones - semipelitic - Sj

MUDJATIK DOMAIN MUDJATIK - with granite, massive to massive granite, with - W calc-silicate lenses; calc-silicate Tk garnet; - with calc-silicate and biotite calc-silicate with - aplite 0 tourmaline; pegmatite zones tourmaline ’ 0 gneiss with granodiorite diatexite granodiorite gneiss with Nk ’ - with marble calc-silicate lenses; calc-silicate W 01 O 01 Kj - with tonalite; with - 0 O - with albite-pyroxene rocks albite-pyroxene with - ’ W 0 garnet; ’ 102 Kl aplite Nn 00 102 O W 00 W O pegmatite zones 60 59 - with biotite with gneiss; psammite - f - pink granite, fluorite bearing; fluorite pink granite, f - Nh G aplite W - granite and Hurwitz Group metagreywacke, Group and Hurwitz granite - b - biotite-psammite gneiss, biotite-psammite b - rock; albite with pyroxene k - S S f - tonalite to granodiorite, + fluorite tonalite tof granodiorite, - diatexite to biotite metatexite, paragneiss to schist and interlayered impure quartzite impure to schist and interlayered paragneiss semipelitic paragneiss to metatexite;semipelitic paragneiss T tonalite; biotite gneiss; psammite foliated, psammite gneiss; Granite; diatexite to biotite-metatexite granodiorite gneiss tonalitic to grey granodioritic with Granite porphyry feldspar Quartz bearing Tonalite, cordierite Dolomite Argillite metasiltstoneMetagreywacke, Biotite gneiss, psammite rocks Calc-silicate rocks Albite-pyroxene toSemipelitic metatexite, paragneiss + garnet; diatexite to biotite metatexite, Granodiorite Amphibolite gneiss; tonalitic to granodioritic Grey tonalite gneiss and granite Cataclastic to grey granodioritic Diabase foliated, to massive Granite, bearing, Tonalite, cordierite metatexite; gneiss with arkosic derived Meta-arkose; W W rock; Calc-silicate tremolite quartz Marble rock; Albite-pyroxene toSemipelitic metatexite, paragneiss + garnet; to quartzite quartzite Impure Foliated granite tonalitic to granodioritic Grey to biotite metatexite, (monzocharnokite) granite Hypersthene calc-silicate and biotite psammite gneiss and biotite psammite calc-silicate massive to foliated, massive Gw metasiltstone silicate layers albite-pyroxene rocks albite-pyroxene SYMBOLS b o x K K K K K N N Q P W S Sn T T A R D D G G G Tj Tk Z Tn H Gh Gn W W W W W H W W W H W W Hudsonian Group Hurwitz Group Wollaston Post-Hudsonian Group Wollaston Hudsonian Contact: defined or approximate Contact: defined or Contact: gradational data aeromagnetic from Contact: inferred water under Contact: inferred: Contact: assumed Fault: approximate defined or Fault: assumed boundary Domain Esker outcrop of no Precambrian littleArea or Bedding, inclined, tops dip unknown vertical, unknown; schistosity;Bedding, and parallel inclined, tops unknown dip unknown vertical, inclined, dip unknown vertical, layering; Metamorphic Schistosity; inclined, dip unknown vertical, gneissosity; inclined, and parallel layering Metamorphic dip unknown vertical, schistosity; and parallel inclined, layering Metamorphic dip unknown vertical, Gneissosity; inclined, dip unknown vertical, foliation,Cataclastic dip unknown vertical, MUDJATIK DOMAIN Proterozoic Archean and/or Proterozoic Archean DOMAIN WOLLASTON Proterozoic Archean and/or Proterozoic Archean 29’ E

O

9 Magnetic North Magnetic North (2000) for(2000) centre of map Decreasing 10.4’ annually 10.4’ Decreasing Approximate mean declination mean Approximate 0 O 0 ’ 0 59 ’ 0 0 0 O ’ O 6550000 66 000

00 15 60 Printed 2005 Printed 0 30 100 O 6650000 45

N Lake W N Nn b W W G 100 Kb S Nn Sn G Nn

W Lake W W W k 0 W 50 S G

-50 Egenolf 800 600 500 400 350 300 250 200 150 100 W Gh -100 -150 -200 -250 -300 -350 -400 -500 1000 T Gammas

Nn Shannon W Sn W G 0 Gp G ’ G 0

RIVER ’ k 00 Nn S O b 0 00 Nn W ’ O S W 0 k W ’ 59 W 00 60 G O G T 00 O

Gp Lake T 100

100 Lake

Sn Minuhik W Nn

T Nahili W

Q W SEAL Nn T W G T N Gp Nn W N T W W T

N

N W River W

Gp

Nunavut Manitoba N W

k T NORTH G f T Nh 0 Tn ’ W N 0 ’ W 30 N W 30 Nh Nh W W

10 T o p p L a k e p l u t o n o t u l p e k a L p p o T k Nh W S Sn Km0 1020304050Km W Sn W W

RESIDUAL TOTAL FIELD SHADED RELIEF Thlewiaza Nh Gp

W Lake

Tn

Koona Lake 0 Trade and Mines, scale 1: 250 000. Series, NTS 64N, Compilation Map Manitoba Geological Survey, Bedrock Geology ’ T N 0 ’ Thomas Nk 01 W W O 01

Q 0 O

MacMillan Lake Gw ’ W T 0 Synoptic geology by D.C.P.W. Schledewitz, Weber, C.F.and Lamb K.A. Compilation by D.C.P. Schledewitz and D. Lindal Digital CAD drafting by B. Lenton GIS cartography by L. Chackowsky Suggested reference: Manitoba Industry, Trade and Mines 2000: Lake; Kasmere Manitoba Industry, Published by: Manitoba Industry, Trade and Mines Manitoba Geological Survey, 2000 Every possible effort has been made to ensure that the information presented on this map is accurate. However, the Province of Manitoba and Industry, Manitoba Trade and MinesReferences are included for users wishing to verify information. do not assume liability for any errors that may occur. ’ 102 00

102 Putahow O 00 O T 60 59 Tn Sn N K W 000 Q W W T W W 00 H 4 Sn Gp W Nh W Tn N b W 000 S Sn 00 W W 4 in in K W Nh Nl b W S W b

River northern W S K b k N b W W S S N W S x W W W W Z Q W N K Hudson Orogen; W W Hudson hinterland, W las Lake area (west

Whitmore

Tn Lake Sn Radiogenic Age and Report of Activities, H W K in Hudson orogenic belt,

W in Thlewiaza Nh K k b W W S S k W W S W Gj W H Munroe Lake area, northwest D Lewry, J.F. and Stauffer, M.R. 0 0 W O O G in H Gp 101 101 G N Nk W Nl W Sn b D W W S Gj Hudson Orogen in northern Saskatchewan, W x Nn G W Z Nl b N Gn Nl S W Scale 1:250 250000 W W W K W

R i v e r K W the western Churchill province and its significance; k Nn S D G W W

T Lake b uton, Kamilukuak Lake area, of Keewatin, estabishes G a Bulletin, v. 104, p.1073-1085. S T

L A K E R.D., and Eickard, D. (eds.): Geochemistry Mineralization Nn Hudson Orogen of North America; Geological Association

mation in the Cook Lake area, Wollaston domain, northern Tice W Hudson Orogen, northern Saskatchewan, ; Canadian P u t a h o w W Nk Whiskey Jack Lake (north half) area (Kasmere project); Manitoba W Nn Nj G W W K N ory of the Wollaston, Peter Lake, and Rottenstone domains in N W W T Tn W

K A S M E R E Tn x Sn Z G es, v. 12, p. 1749-1759. W Summary of Investigations 1997, Saskatchewan Geological Survey, Gn G T G Tk G Nj N W Nn in W 5 Nn Gn Kj W W W N Pharoh, T.C., Beckinsle, scintillometer and lake sediment surveys, Kasmere- G

R i v e r W K G Sn W in Current Research, Part B, Geological Survey of Canada, Paper 85-1B, p. 367-370. thaman batholith: an early Proterozoic continental arc in the Trans- K W Gn A W N Fort Hall Fort

Lake W N in A K Pb age on zircon from a quartz syenite intrusion, Amer Lake map area, District of Keewatin, W W A b Kilometres 0 5 10 15 20 25 Kilometres Tk S Ayres, L.D., Thursont, P.C., Card, K.D., and Weber W. (eds): Evolution of Archean Supracrustal Sequences; Geological Association of Canada, Special Paper 28, p. 239-261. Canada; of Proterozoic Volcanic Suites; Geological Society London, Special Publication 33, p. 147-166. (eds.): The Early Proterozoic Trans- Canada, Special Paper 37, p. 1-14. a lower limit for the age of Christopher Island formation, Dubawnt group; Isotopic Studies: Report 1; Geological Survey of Canada, Paper 87-2, p. 67-71. Geochronological studies of Precambrian rocks from the southern District Keewatin; Geological Survey of Canada, Paper 88-18, p. 36. Saskatchewan; Saskatchewan Energy and Mines, Misc. Report 97-4, p.115-120. The Wa Canada; Geological Society of Americ half), Sandfly Lake area (east and Black Island (west half); Saskatchewan Department of Mineral Resources Report 88, p. 70. Canada; Geology, v. 19, no. 11, p. 1137-1140. Report of Activites,1994,Manitoba Department Energy and Mines, p. 5-10. Saskatchewan; Canadian Journal of Earth Sciences, v. 17, p. 333-347. Geology of the Cochrane and Seal area; Manitoba Energy Mines, Geological Services; Geological Report GR80-9, p. 139. Manitoba; Manitoba Mineral Resources Division, Economic Geology Report ER80-2, 35 p. Canadian Journal of Earth Sciences, v. 30, p.1338-1354. NWT; Journal of Earth Sciences, v. 24, p. 407-424. 1986, Manitoba Department of Energy and Mines, Report Field Activities, 1986, p. 207-210. Department of Mines, Resources and Environmental Management, Mineral Division, Geological Services Branch, Publication 74-2, p. 163. Geology and geochronology of the Wollaston Lake fold belt in northwestern Manitoba; Canadian Journal of Earth Scienc W T K G W J.F., Macdonald, R., Livesey, C., Meyer, M., Van Schmus, W.R., and Bickford, M.E. G Tn K N

N

W

W

Kj r

e Kj W v 1990: The Trans-Hudson Orogen: extent, subdivision, and problems; 1987: age on zircon from a granite pl A U-Pb 1988: 1997: Geology of the Courtenay Lake for 1992: 1965: The geology of the area around Needle Falls, Churchill River, comprising Eu 1991: New geological limits on the depositional age of HurwitzTrans- group, 1994:Manitoba; northwest ES-C, and Mineral resource studies in proposed endangered spaces, ES-A 1980: The age and geological hist 1986: 1980: Helicopter- 1993: Regional setting and kinematic features of the Needle Falls shear zone, Trans- 1985: A U- 1987: U-Pb geochronology in the Trans- 1986: U-Pb zircon geochronology of the Big Sand Lake area in northern Manitoba; 1975a: Geology of the Kasmere Lake- 1975b: 1987: U-Pb geochronolgy of accreted terranes in the Trans- 1985: Variation in character of Archean rocks i

W R

W

A a

Thanout z G

a

G i

Nn w A

e Lewry, Lewry, J.F. and Collerson, K.D. Loveridge, W.D., Eade, K.E., and Roddick, J.C. Loveridge, W.D., Eade, K.E., and Sullivan, R.W. MacNeil, A., Delaney, G.D., and Ansdell, K. Meyer, M.T., Bickford, M.E., and Lewry, J.F. Money, P.L. Patterson, J.G. and Heaman, L.M. Peck, D.C., Cameron, H.D.M., and Hosain, I.T. Ray, G.E. and Wanless, R.K. Schledewitz, D.C.P. Soonawala, N.M. Stauffer, M.R. and Lewry, J.F. Tella, S., Heywood, W.W., and Loveridge, W.D. W.R., Bickford, M.E., Lewry, J.F., and Macdonald, R. Van Schmus, Van Schmus, W.R. and Schledewitz, D.C.P. Weber, W., Schledewitz, D.C.P., Lamb, C.F., and Thomas, K.A. Weber, W., Anderson, R.K., and Clark, G.S. Lewry, J.F., Sibbald, T.I.I., and Schledewitz, D.C.P. G l

R h P a r t r i d g e G T W N G N N G W Sn N G W

Fort Tk W W W Sn b W Sn S Sj 0 K W N ’ W W

Lake W A Tk W

Hall Nn T 0 b b ’ S Tn W S Tn W

L i t t l e River W 30 Tk G 30 Summary of K Thlewiaza Summary of N W Sj in G Lewry, J.F. and W W Tn b SELECTED BIBLIOGRAPHY in K G S Current Research, W in K W W K in W Tj b Lewry, J.F. and Stauffer, S 000 N W Tj Sn W T 50 in 3 W Tk N

Lake G Tk W Tk K K

000 Erickson N W v. 24, p. 1053-1063. W

W Snyder G 50

Lake G 3 Tk Tk G T b S W T domain, northern Saskatchewan; W.R., and Chiarenzelli, J.R. W.R., and Tj K Earth Sciences, Gh W province in northern Saskatchewan; Tectonophysics, v. Nn Sj W ozoic calc-alkaline plutons northwest of , District x W Z Summary of Investigations 1997, Saskatchewan Geological o in D f H Nn W G K -Griffin lakes area, District of Keewatin, N.W.T.; W their relation to tectonism and plutonism in the Churchill province Metamorphism in the Canadian Shield, Geological Survey of Canada, f me granitoids from the Peter Lake domain: a summary; Tk Nn Summary of Investigations 1995, Saskatchewan Geological Survey, G b in Tk S W P of thermotectonic events in the Wollaston Lake area, domain: a W H in b f S N Nn G W W W Tn G P Current Research, Part 1A, Geological Survey of Canada, Paper 87-1A, p. 773-782. Th hology and tectonometamorphic relationships in the Precambrian basement of H P H Tk G in o Current Research, Part C, Geological Survey of Canada, Paper 89-1C, p. 143-155. 0 D O N H in

W f o

D

G Manitoba x

H

Z 0

102 50 000 66 O

Th

0

00 000 O 66

0 Saskatchewan

’

0 Lake area, District of Keewatin, and the shelf to foredeep transition in foreland Trans-Hudson Orogen; the Hurwitz Group, Hawk Hill Part C, Geological Survey of Canada, Paper 90-1C, p. 219-230. summary of 1994-1996 results; Energy and Mines, Misc. Rep. 97-4, p. 162-173. Survey, Saskatchewan Proterozoic magmatism; Canadian Journal of p. 14-18. domains, Churchill province, northern Manitoba, Canada; Canadian Journal of Earth Sciences, v. 24, p. 246-254. Sciences, v. 13, p. 355-364. embayment, Johnson River inlier, Wollaston Investigations 1992, Saskatchewan Geological Survey, Energy and Mines, Misc. Report 92-4, p. 168-171. Investigations, 1997, Saskatchewan Geological Survey, Energy Mines, Misc. Rep. 97-4, p. 90-101. 70-45, p. 19. Geological Survey of Canada, Paper 72-21, p. 29. Lithogeochemistry of volcanic rocks from the lower Proterozoic Courtenay Lake formation, Lake Courtenay Proterozoic Lithogeochemistry of volcanic rocks fromlower the Wollaston Domain; Saskatchewan Energy and Mines, Misc. Report 95-4, p. 49-60. Thorsteinson, and Baldock batholiths, Churchill province, Manitoba.; M.R., eds., The Early Proterozoic Trans-Hudson Orogen of North America; Geological Association of Canada, Special Paper 37, p. 201-214. Stauffer, M.R. (eds.): The Early Proterozoic Trans-Hudson Orogen of North America; Geological America; North of Stauffer, M.R. (eds.): The Early Proterozoic Trans-HudsonOrogen Association of Canada, Special Paper 37, p.15-39. of Keewatin; northern Saskatchewan; Canadian Journal of Earth Sciences, v. 14, p.1453-1467. northern Saskatchewan; Paper, 78-10, p.139-154. 68, p. 45-82. 50 000 65 102 ’ 0 60 ’ 0 O 45 59 30 1992: U-Pb geochronology of so 1997: U-Pb geochronology 1989: belt, thrust-fold Sedimentology, structure, and economic geology of the Poorfish-Windy 1990:in gold for implications and Stratigraphy, sedimentation, dome and basin basement-coverinfolding, 1987: U-Pb zircon ages from the Lynn Lake and Rusty metavolcanic belts, Manitoba: two of 1990: Proterozoic collisional tectonism in the Trans-Hudson Orogen, Saskatchewan; Geology, v.18, no. 1, 1988:Island Rubidium-strontiumGreat ages of Archean and Proterozoic rocks in the Nejanilini 1976: Rb/Sr dating of rocks from the Wollaston Lake belt Saskatchewan; Canadian Journal Earth 1997: Geological investigations of the Lake fold belt and the Hills Courtenay Lake-Cairns 1971: Geology of the map-area, District of Keewatin; Geological Survey Canada, Paper 1973:Keewatin; of District Geology of the Nueltin Lake and Edehon (west half) map-areas, 1995: 1990: Trace-element and Rb-Sr whole-rock isotopic constraints on the origin of , 1990: Subdivision of the Churchill province and extent Trans-Hudson Orogen; 1987: Geology and U-Pb ages of early Proter 1977: Variation in lit 1978: Metamorphic patterns and 1980: Thermotectonic evolution of the Churchill 15 Universal Transverse Mercator Projection Mercator Transverse Universal 14Zone North American Datum1983 Annesley, I.R., Madore, C., and Krogh, T.E. Annesley, I.R., Madore, C., Rupan, S., and Krogh, T.E. Aspler, L.B., Bursey, T.L., and Miller, A.R. Aspler, L.B. and Bursey, T.L. Baldwin, D.A., Syme, E.C., Zwanzig, H.V., Gordon, T.M., Hunt, P.A., and Stevens, R.D. Bickford, M.E., Collerson, K.D., Lewry, J.F., Van Schmus, Clark, G.S. and Schledewitz, D.C.P. Cummings, G.L. and Scott, B.P. Delaney, G.D., Janovic, Z., MacNeil, A., McGowan, J., and Tisdale, D. Eade K.E. Eade K.E. Fossenier, K., Delaney, G.D., and Watters B.R. Halden, N.M., Clark, G.S., Corkey, M.T., Lenton, P.G., and Schledewitz, D.C.P. Halden, N.M., Clark, G.S., Corkey, M.T., Lenton, P.G., and Schledewitz, Hoffman, P.F. Le Cheminant, A.N., Roddick, J.C., Tessier, A.C., and Bethune, K.M. Lewry, J.F. and Sibbald, T.I.I. Lewry, J.F., Sibbald, T.I.I., and Rees, C.J. Lewry, J.F. and Sibbald, T.I.I.

tory. 58 8 Ma canic , and ± logical Cairns ). The ). The ) of the ing of 5 Hudson

directed 59 trending dle Falls N ) and the ples were proximate Zx Sb W N W r Hudsonian W silicate rocks,

. Broad zones

57

54K

Paleozoic 94

bearing and with

Bay Churchill Juvenile Paleoproterozoic rocks Parker Shear Zone Lake Great Island

Fergus River Shear Zone Fergus Reilly Lake Shear Zone Hudson

h the south end of 60 1800 Ma; Bickford et bearing minerals and the Paleoproterozoic GI derived paragneiss and RLSZ PLSZ FRSZ

Chipewyan magmatic arc 54L silicate rocks that contain a Courtenay Lake Formation biotite gneiss and the white Hudson Orogen sedimentary pelitic to gneiss in the

dome polyphase deformation. 54E ld trend and the easterly Seal

The Manitoba segment of the 54M silicate metasedimentary rocks k and Schledewitz, 1988). A up was carried out by mining

ium to thorium. The URP survey 96 Hearne craton and an accreted derived gneisses of the Wollaston floor rocks and intrusive (the ) or biotite psammite gneiss (unit Sr ages in northern Manitoba are Sr are characteristic of plutons in the Sn is recorded in felsic volcanism the ately 100 km. The Wollaston Domain pelitic to gneiss and intruded by

86 Block

W

GI Ennadai sediment sampling, with an ap

Sr/

Nunavut -type Wathaman- Manitoba

domes, antiforms and synforms that are

64H 64I

87 64P margin magmatic arc related to a northerly Hudson Orogen. This collision belt extends for

Seal River Domain and the Nejanilini Domain. 98

silicate rocks. A sedimentary origin is the preferred 100 Great Island Group - IslandGreat overlies Group metavolcanic rocks at and east of Great Island Pre- Great Island Great Pre- Group quartz diorite Paleoproterozoic intrusions ) and the basal garnet- biotite gneiss (unit K 1812 Ma; Annesley et al., 1997) is similar to the age of

W

64G 64O

32 Ma (initial ratio 0.7113; Weber et al., 1975b). This age

km 64J was a nation-wide survey carried out by the Geo ± ). These rocks exhibit a uniform low magnetic signature share a common lithostratigraphy and metamorphic his 17 Ma (Patterson and Heaman, 1991) intrude Hurwitz Group T Saskatchewan border, where it is approximately 90 km wide been further deformed by discrete northerly and northeasterly

PART OF TRANS-HUDSON OROGEN

Wathaman - Chipewyan Magmatic Arc Magmatic Chipewyan - Wathaman 0

to the west at Bagg Lake, in Kasmere Lake map area (NTS FRSZ

separated by the Andean

100 Hearne

Hudson plutonism in the Lake zone contained a much larger Province of the of Province

rocks (Manitoba) overlie garnet-biotite gneiss (age uncertain).

Rae- Hearne craton Hearne Rae-

64F

Lynn Lake Domain Lake Lynn 64K 64N

, was carried out as part of a concurrent geochemical survey. Sam mere Lake map area, NTS 64N). Northeast of Kasmere Lake, the Wollaston 2 Zone Shear

Chipewyan magmatic arc at 1865 to 1855 Ma (Van Schmus and Schledewitz,

dome pattern continues to the southwest into Whiskey Jack Lake map area

) that occupies the southeast quarter of Kasmere Lake map area. Snowbird Co lake sediment geochemical anomaly restricted to the region extending from Nunavut

Ameto Formation (Hurwitz Group) and the overlying Kiyuk Group. The entire

Gp N.W.T. nison Mines Ltd., Dynamic Petroleum Ltd. and Antimony Corp. (Weber Manitoba Saskatchewan

occurs east of the Wollaston Domain. It is characterized by large, to east- 102 along the eastern edge of Wollaston Group in Saskatchewan, also contain a Ensialic Zone Mobile uncertainParagneiss, age sonian Topp Lake pluton, a large, Paleoproterozoic, synkinematic, porphyritic Archean, altered, abundant Paleoproterozoic intrusions is defined by 1) the predominance of supracrustal-

belt structural style. These criteria were first established in Saskatchewan and termed bearing amphibolite after gabbro (Peck et al., 1994). The highly varied magnetic

pelitic to gneiss in the core of synform is anomalous; regionally, paragneiss x

64E e RLSZ

l

km wide (Kas p

) that most commonly intrudes the garnet-biotite gneiss. uncertain reworking of degree

silicate rocks. Synforms in general are highly tightened and the trends of axial traces m

64L o 64M

cally low magnetic intensity. The data suggest that the paragneiss may form a thin T

La Ronge - Southern Indian Domain Indian Southern - Ronge La C

metal occurrences interpreted to fit a sedimentary exhalative origin (Delaney et al., 1997).

Chipewyan magmatic arc lies between the Archean Rae- e

the semipelitic to pelitic gneiss. The origin of 50 km long easterly trending magnetic k

a

rrhotite- tectonites

L

PLSZ

r

e

t

e P Zone, whereas the south flank of magmatic arc has lower initial ratios (Halden et al., 1990). Hudson Orogen, the Cree Lake Ensialic Mobile Zone of Archean Hearne Province, and 2)

arc terranes. Plutons with this tectonic relationship occur in the Seal River Domain and at 104 rized in Schledewitz (1986) and Soonawala (1980). Montgomery Group and Hurwitz Kinga formations, the overlying Ameto Formation (Nunavut), range in age from 2400 to 2100 Ma (Patterson and Heaman, 1991), possibly represent cratonic-basin sedimentation (Aspler and Bursey, 1990). Wollaston Group Courtenay Lake Formation (Saskatchewan), with a minimum age of 2100 Ma (Annesley et al., 1992), unconformably overlies garnet-biotite gneiss (age uncertain). Kinga Formation (Nunavut). lower Ameto Formation and underlying Mafic pillowed and massive flows in the Courtenay Lake Formation (Saskatchewan) have a minimum age of 2100 Ma (Fossenier et al., 1995; Annesley 1992). deformation of cratonic basin and (?) passive margin successions into fold thrust belts, overthrusting of (?) fore-deep deposits; on synkinematic tonalitic gneiss which postdate some phases of deformation (Lewry et al., 1987). Shear Zone (an oblique collision structure), 1855 to 1800 Ma (Stauffer and Lewry, 1993) at the boundary with the Wollaston Domain and along shear zones at boundary Peter Lake Complex (Reindeer Lake, Saskatchewan). The age of peak thermal metamorphism the Wollaston Group, underlying Archean basement, and Hudsonian intrusions (ca. 1820- early-formed peak metamorphism in the Trans-Hudson Orogen south of the magmatic arc. Ductile/brittle deformation continued along the Needle Falls Shear Zone and mostly sheared boundary of the Peter Lake Complex (Ray and Wanless, 1980; Van Schmus et al., 1987). magmatic arc, structures of the Wathaman-Chipewyan nies, the Manitoba Mineral Resources Division and Geological Survey of Canada. This activity is - Mafic sills and flows, dated at 2094 +26/- - - Wollaston Group calc-silicate - - and metamorphism in the Rottenstone Domain (Saskatchewan) minimum age 1867 deformation - - - tFolds tightened and ductile/brittle shearing occurred in the Wollaston Mudjatik domains. - and east-trending ductile/brittle shear zones were superimposed on the east- Northeast-, north- - - - The northwest margin of arc is deformed along the Nee the Wathaman-Chipewyan magmatic lated to opening of the Manikwan Sea (Patterson and Heaman, 1991; Aspler Bursey, 1990). Units

).

Rae

Pre-Trans-Hudson Orogen mafic igneous and volcanic rocks (geochemistry favours continental-rift setting): Zone Shear The earliest dated magmatism related to Trans-Hudson orogenesis Late to postcollisional deformation: Postcollisional granites (1753 +3/-2Ma; Loveridge et al., 1987), characteristically fluorite- Pre-Trans-Hudson Orogen sedimentation: Emplacement of Wathaman- Continent-continent collision, deformation and emplacement of nappe sheets (1830- Lynn Lake belt at 1.91 Ga (Baldwin et al., 1987). The mafic igneous activity ca. 2100 Ma may have re the deposited Trans-Hudsonwithin Orogen may have been limited to post- (Wollaston Group), post- Trans-the Paleoproterozoic cover sequence and Archean infrastructure was deformed during orogenesis. Possible early arc-continent collision (1888-1860 Ma; Bickford et al., 1990): 1986; Meyer et al., 1992) is interpreted as a continental- subduction flip. al., 1990): rapakivi texture and high uranium background, occur most commonly in parts of the Hearne Province where negative gravity anomalies exceed -60 mGals (Schledewitz, 1986). Wollaston Group Wollaston

Sb

Province of the of Province Bear River Bear

Southwest of the Topp Lake pluton, structure is characterized by basin-and- • • A complex collage of Paleoproterozoic volcanic island arc, back-arc-ocean- • • The known base-metal occurrences are mainly in the calc- The known base-metal Wollaston Group paragneiss unconformably overlies Archean granitoid rocks and possibly vol and sedimentary-derived gneiss. The Wollaston Domain is a northeast-trending fold belt with mino plutonism, whereas the Seal River Domain exhibits an early, easterly trending, open fold set locally overprinted by northeasterly structures. The Seal River Domain contains a greater volume of Hudsonian plutons. The Wollaston Domain Group, and 2) the fold- the Wollaston Fold Belt System (Money, 1965) with a width of approxim in Manitoba is well defined from the Manitoba- (Whiskey Jack Lake map area, NTS 64K) and trends northeasterly to the south end of Kasmere Lake, where it is approximately 35 Domain is less well defined and narrows to 20 km at the Nunavut border. by tightly spaced elongate Wollaston Domain is characterized generally tight to isoclinal. The antiforms contain cores of pelitic and semipelitic gneiss (unit (unit monzocharnockite to enderbite elongate domes are cored by Archean hypersthene-bearing (unit synforms contain in their cores Wollaston Group meta-arkose W trending structures. Based on magnetic trends and attitudes of metamorphic layering, the western boundary the Seal River Domain is irregular and step-like, reflecting a pattern of structural interference. The west end of the Seal River Domain, for a distance approximately 40 km to east, is divided into two segments by the Hud monzogranite intrusion (unit This fold pattern is the result of interference northeasterly Wollaston fo supracrustal- of layering River fold trend. Major structures are outlined by large-scale migmatite. Domes are cored by Archean and/or Hudsonian granitic rocks. The basins arkosic gneiss and/or calc- highly variable. This basin-and- (NTS 64K). 40 km wide synform cored by semi- An easterly trending, approximately variably magnetic pink monzogranite, lies on the north flank of Topp Lake pluton. The south limb psammite gneiss (unit and biotite synform comprises magnetiferous arkosic gneiss, calc-silicate north limb of the synform comprises magnetiferous arkosic gneiss, and calc- intruded by py signature of the semi- has a characteristi arkosic gneiss. The presence of the basal semi- cover overlying magnetiferous core of the synform overlying younger arkosic gneiss, uppermost unit Wollaston Group, is evidence of a structural inversion. The easterly trending synform is truncated 64N) and trends westerly into the Munroe Lake map area (NTS 64O). The north limb of synform coincides with a 50 km long, easterly trending series of strong magnetic linears that passes throug Nueltin Lake. Rocks north of the easterly trending magnetic lineament include semipelitic to pelitic garnet- biotite gneiss, intruded by white tonalite (unit characteristic of lineament along the north limb of synform remains unresolved. Economic Geology The Uranium Reconnaissance Program (URP) Survey of Canada, with Manitoba participating in 1975 and 1976. The survey was flown on a line spac spectrometer. Lake-centre gamma-ray km, using a high-sensitivity density of one sample per 13 km analyzed for U, Zn, Cu, Pb, Ni, Co, Ag, Mn, Fe, Mo, As, Hg and loss-on-ignition. The URP was intended to define broad regions containing higher than average uranium contents of uranium enrichment were delineated in northern Manitoba, mainly the Kasmere Lake map area. The potential for uranium deposits in this area was originally indicated from limited prospecting followed by more extensive exploration, by De et al., 1975a). Between Snyder Lake and Kasmere the survey revealed a chain of lake sediment anomalies, trains of radiometric anomalies and relatively higher ratios uran also indicated a complex U-Ni- Snyder Lake to Fort Hall and Thanout lakes. The anomalies can be related calc- larger than average component of amphibolite and uniquely contain cobalt-and nickel- trace amounts of gold. rocks (unit Uranium occurs in both the calc-silicate Wollaston Group. However, concentration levels are higher and more localized in the calc- compared to the more widely dispersed lower levels of uranium in garnet- leucotonalite (unit interpretation for the base metal occurrences (Weber et al., 1975a). The rocks of Courtenay Lake- Lake fold belt, which lie number of base- Mineral showings and deposits in Saskatchewan occur sporadically over a distance of 280 km. Subsequent to the release of URP survey, extensive ground follow- compa summa Tectonic Synthesis The rocks of the Kasmere Lake map area are part Trans- approximately 5000 km from United States, through the Churchill Province in Canada the north-central ultimately to Greenland (Lewry and Collerson, 1990). In Manitoba Saskatchewan two major elements of the Trans- Paleoproterozoic arc-related terranes, are which ha • The Wathaman- The Seal River Domain southeast trending folds and faults that have The Wollaston Domain and Seal River Rae- Hearne craton Hearne Rae-

Shear Zone Shear cratonic zone cratonic

Archean, undivided Hurwitz Group tectonites Wollaston Group

Needle Falls Needle

Athabasca Basin Athabasca

LITHOTECTONIC ELEMENTS OF Zone Shear Grease River Grease ± f), ) in G W ). H ) in the Sn MARGINAL NOTES Do W ) occurs in Chipewyan H ) to a stage K Do ) and a locally H W . Both of these man- Sb lits W ) remains uncertain. N 0 0 0 0 0 0 O O O O O O W 59 57 55 53 51 49 0 O the Watha 88 bearing marble and an albite- -biotite gneiss along the north ), dated at (1850 to 1823 Ma ; ) and dolomite (unit diopside gneiss (unit 18 Ma and 2777 +95/-66Ma ) has been tentatively correlated ± P ± G W tzite matrix. These rock types are H H 0 O of supracrustal-derived garnet-biotite 6). The calc-silicate rock comprises rock 6). The calc-silicate scapolite layers and carbonate tremolite- 92 ± ± ) overlain by dolomite (unit P

to the south by

H ) is overlain by a compositionally variable River hornblende 0

the point of bifurcation. Aeromagnetic trends N O ± Ontario ) overlies magnetic quartz diorite to granodiorite H U D S O N B A Y W 92 KILOMETRES W

H NORTHERN SUPERIOR

Gods

River LAKE ZONE Granite- greenstone Granite- Batholithic granite and granite Batholithic gneiss granitoid Sedimentary gneiss/migmatite Sedimentary Trans- Hudson Orogen Hudson Trans- Archean) (Proterozoic- Province Structural Superior (Archean) Cenozoic Mesozoic Paleozoic ) and the Hurwitz Group metagreywacke (unit ilmenite and sphene. The suite of calc-silicate rocks is ilmenite and sphene. The suite of calc-silicate

0 50 100 150 200 250 River

Sb

Hayes

Churchill Lake

W Gods Phanerozoic Precambrian

P A L E O Z O I C Lithostructural belts & domains

Lake the Ennadai Lake area (Nunavut). Eade (1971) considered River

crystallization age, was obtained from samples of mylonitic KISSEYNEW

River Island ages of 2.9 to 2.7 Ga (Bickford et al., 1990). The Archean rocks 0 O UCHI

laston Group in Manitoba correlates with the change from cratonic BOUNDARY GODS 0 RIVER GREAT ISLAND O

96

LAKE

ISLAND WABIGOON

WINNIPEG Winnipeg Churchill Nelson BIRD RIVER BIRD 96

River

) interpreted to have been deposited in a platform setting (Weber et al.,

RIVER

BERENS Minnesota

K

unknown and has been inferred to be Paleoproterozoic but the possibility River

ASSEAN LAKE ASSEAN NEJANILINI W

is related to an array of east-northeasterly trending shear zones rooted in rooted zones shear trending is related to an array of east-northeasterly PIKWITONEI

) in Manitoba is underlain part by mylonitic to protomylonitic granodioritic Nunavut

Seal

ENGLISH RIVER

). It contains sporadic interlayers of calc-silicate rocks and impure to pure to impure and rocks ). It contains sporadic interlayers of calc-silicate Red MOLSON LAKE MOLSON WINNIPEG P regions, the Ennadai Block (Lewry et al., 1985), trends southwesterlyfrom N ) in the Wol ) H W

Southern

Indian Sb

MESOZOIC

SUPERIOR C W River

Lake aman-Chipewyan batholithic domain. I

WINNIPEG O

Thompson LAKE Z 0 k) in a shear zone that is 2 to 9 km wide and trends southwesterly into Saskatchewan.

O O ) and minor zones, occurring in the Wollaston Domain from Tice Lake calc-silicate was defined in Saskatchewan (Lewry and Sibbald, 1977) is characterized by flat- T E

LAKE

LYNN LAKE L C H I P E W Y A N

W Wollaston Group Relationship Wollaston Assiniboine 100 A North Dakota MANITOBA H

CENOZOIC P 0

PRINCIPAL GEOLOGICAL DOMAINS Brandon O

SEAL RIVER The syncline is the southerly part of a larger, complex, bifurcating synclinal structure that Lk

Cedar 100

) along and immediately northwest of the eastern boundary Mudjatik Domain.Magnetic R an LAKE

w

-Hearne craton. The Snowbird Shear Zone divides the Rae-Hearne craton into the Rae Province Rae the into craton -Hearne craton. The Snowbird Shear Zone divides the Rae-Hearne WOLLASTON e Reindeer MUDJATIK FLIN FLON h Lake WINNIPEGOSIS Tn Sr ratios for these rocks suggest that a component of their sedimentary provenance was Archean; tc

Lynn Lake a

KISSEYNEW k

SOUTHERN INDIAN 86 s a

The Pas M E S O Z O I C

Flin Flon S cordierite gneiss (unit Saskatchewan Sr/ 3 Ma, interpreted to be an igneous ± ± 87 0 0 0 0 0 0 O O O O O O 59 57 55 53 51 49 northeasterly through the area of Putahow Lake into Nunavut. This unit ( unit This Nunavut. into Lake northeasterly through the area of Putahow the greywacke to be part of Ameto Formation and possibly time equivalent argillite. Wollaston Group garnet- The basal unit of the Wollaston Group in Manitoba and Saskatchewan is a psammitic to semipelitic biotite quartzite. The gneiss shows a well developed metamorphic layering defined by alternating grey to dark grey, granitic coarse-grained layers (1-100 cm thick), and white to cream, medium-to biotite-rich components are intruded by white, pegmatitic, boudinaged sills of granite. Areas underlain these rocks coincide with areas of low magnetic intensity (2000-2200 gammas). minor a is sillimanite Garnet and cordierite are common accessory minerals in the garnet-biotitegneiss; component and occurrences of hypersthene andalusite are more localized (Schledewitz, 1986). Hypersthene or rocks occurs granitic in gneiss that is underlain by either hypersthene-bearing the semi-pelitic extreme northwest corner of the Kasmere Lake map area in Manitoba and along eastern boundary extreme Mudjatik Domain. The Hurwitz Group rocks have been folded into a syncline that extends southwesterly Saskatchewan. extends into Nunavut where it is cored by post-Hurwitz Group rocks of the Kiyuk (Aspler et al., 1989). A granite occupies a domal structure at pluton of fluorite-bearing indicate that the Hurwitz Group in northeastern Saskatchewan forms a closure, and two synclines converge. The complex synclinal structure is considered to be at the southeasterly termination of a segment the Archean infrastructure, the Ennadai Block (Lewry et al., 1985), that is characterized by a lesser degree of reactivation than elsewhere in the Mudjatik Domain. The nature of transition from structural style Ennadai Block to that of the rest Mudjatik Domain remains problematic, due largely to the lack of bedrock exposure. The Hurwitz Group argillite (unit the Kasmere Lake area are considered to be stratigraphic equivalents, based on their lithological similarity and the Kasmere apparent lateral gradation (Weber et al., 1975a). These formations can, in turn, be correlated with the Hurwitz Group Ameto Formation in Nunavut. The Hurwitz and post-Ameto formations define a change from cratonic basin sedimentation (in the underlying Padeli and Kinga formations) to a period of crustal subsidence and tectonic destabilization. Zircon baddeleyite from gabbro sills in the lower to middle Ameto Formation, in the area of North , Nunavut were dated by U-Pb method at 2094 +26/-17 Ma (Patterson and Heamen, 1991). This establishes a minimum depositional age of ca. 2100 Ma for the Hurwitz lower to middle Ameto Formation. By inference, the change from platform sedimentation (unit the Ennadai Block in extreme northwest of Kasmere area. The argillite has been correlated with Tella et al., 1985; Le Cheminant et al.,1987) and anorogenic, high-uranium, fluorite-bearing granite (unit granite fluorite-bearing Tella et al., 1985; Le Cheminant al.,1987) and anorogenic, high-uranium, The Kasmere Lake map area (NTS 64N) lies on the south and east flanks of Hearne Province, part Archean Rae Ameto Formation of the Hurwitz Group in Nunavut (Weber et al., 1975a) and a metagreywacke, with metasiltstone (unit with a similar greywacke of the Hurwitz Group in Archean rocks. Andalusite, very commonly with sillimanite, occurs in the garnet wollastonite lenses. The two other rock types in this suite are quartz white, with discontinuous crudely aligned green to dark layers. The principal minerals are albite and augite to with minor amounts of quartz, aegerine-augite, of economic interest because the observed high concentrations uranium, rare occurrence cobalt- and nickel-bearing minerals, trace amounts of gold. (unit gneiss psammite biotite rocks are overlain by regionally discontinuous The calc-silicate A similar minimum age of 2100 Ma has been established for the Wollaston Group in Saskatchewan. date 2076 quartzofeldspathic gneiss in the rocks of Courtenay Lake Formation Wollaston Group (Annesley et volcanic mafic with al., 1992). Courtenay Lake Formation conglomerate, arkose and quartzite are interlayered rocks characterized by within-plate lithogeochemistry, thus favouring emplacement in a continental rift setting (Fossenier et al., 1995; MacNeil 1997). The timing of continental rifting recorded in the Courtenay Lake Formation in Saskatchewan, at ca. 2100 Ma, is consistent with the observations Nunavut and Manitoba. The Mudjatik Domain screens with lying, migmatitic Archean infrastructural lobes infolded migmatite. Reconnaissance samples of granitoid rocks in the Cree Lake Ensialic Mobile Zone Saskatchewan yielded Archean Sm-Nd model record two main pulses of Neoarchean magmatism, one at 2740 to 2700 Ma and another 2630 2590 Ma, plus an interpreted metamorphic age of 2566 Ma from a migmatitic tonalite gneiss (Annesley et al., 1997). The age of the supracrustal migmatites is of an Archean age cannot be entirely ruled out (Lewry and Sibbald, 1980). The Archean rocks of the Mudjatik Domain in Saskatchewan trend northeasterly into Manitoba. However, Mudjatik Domain changes from a basement-cover mobile belt in Saskatchewan to granitoid Archean infrastructure overlain by metasedimentary rocks of the Hurwitz Group in Manitoba. These rock types were intruded by Hudsonian, synkinematic, moderately uraniferous granite (unit 1975a). Regionally, the calc-silicate rocks occur in Wollaston, Seal River and Nejanilini domains, as bodies of variable size and varied lithologic relationships (Schledewitz, 198 layers with discontinuous diopside amphibole-plagioclase-quartz Hurwitz Group and The Wollaston Group biotite psammite gneiss (unit basin sedimentation in Nunavut. restricted conglomerate comprising calc-silicate and quartz clasts in a quar some in resulted interpreted to mark a change from the platform stage of tectonic disturbance which areas experiencing uplift while other underwent subsidence. The uppermost unit in the Wollaston Group is an areally extensive, pink-weathering, magnetiferous, arkosic to granitic gneiss (unit of tectonic disturbance (unit to the extreme northwest corner of Manitoba. The Hearne Province is separated from accreted Paleoproterozoic juvenile terranes of the Trans-Hudson Orogen to the west and the Hearne Province to the east (Hoffman, 1990). The Archean continental crust of the Hearne varying Province is overlain by Paleoproterozoic cover rocks and, together with the rocks, has undergone Mobile Ensialic Lake (Cree degrees of thermotectonism during the Paleoproterozoic Trans-Hudsonorogeny Zone; Lewry et al., 1978; and Sibbald, 1980). Parts of the Hearne Province are considered to be cratonic or semicratonic with respect to the Trans-Hudson Orogen, since they are little affected by Hudsonian thermotectonism. One of these batholithic domain, which is interpreted as the root of a magmatic arc. The Ensialic Mobile Zone has been subdivided into six domains in Saskatchewan and Manitoba. They are the Mudjatik, Peter Lake (Saskatchewan only), Wollaston, Seal River, Great Island and Nejanilini domains. The Mudjatik and Wollaston domains the west end of Seal River Domain occur in Kasmere Lake map area (NTS 64N). Lithostratigraphy Group and sedimentary-derived gneissic rocks of the Metasedimentary rocks of the Paleoproterozoic Hurwitz Wollaston Group unconformably overlie the Archean basement rocks of Hearne Province. The Hurwitz Group occur almost entirely in Nunavut as discontinuous structural keels along a southeasterly trend from Rankin Inlet to the northwest corner of Manitoba. Hurwitz Group Rocks of the Hurwitz Group are present in northwest corner Kasmere Lake map area, based on mapping and interpretation by Weber et al. (1975a). Argillite (unit pyroxene rock. The marble is best exposed on Fort Hall Lake and Thanout in the Kasmere map rock forms small, sparse area, where it is greater than 45 m thick (Thanout Lake). The albite-pyroxene outcrops that can rarely be traced few kilometres along strike. The rock weathers pale pink to for more than a however, the ratio does not support an Archean age of sedimentation. Nevertheless, the possibility exists that exists possibility the the ratio does not support an Archean age of sedimentation. Nevertheless, however, this rock type may in part be of Archean age (Eade, 1973; Weber et al., 1975a; Lewry and Sibbald, 1980). This possibility is greatest in the Mudjatik Domain (NTS 64K, Manitoba; NTS 64L and 64E, Saskatchewan) Nejanilini Domain (NTS 64O and 64P) where the semipelitic to pelitic gneiss forms enclaves within Archean granitic domains. (unit In the Kasmere Lake area, garnet-biotitegneiss sequence of calc-silicate rocks (unit sequence of calc-silicate flank of the Hudsonian Wath The application of a regionally significant geologic age to the semi-pelitic gneiss (unit The Rb/Sr ages for semipelitic and pelitic rocks of the Wollaston Domain, which range from 1815 to 1835 Ma (Weber et al., 1975b; Cummings and Scott, 1976), are evidence for Paleoproterozoic metamorphism. The high initial gneiss (unit maps suggest that the Hurwitz Group metagreywacke forms a thin cover overling Archean basement of Domain, from Tice Lake through Putahow to the Nunavut border. The Hurwitz Group rocks are Mudjatik openly folded and can be traced north to Kiyuk Lake, Nunavut, into a large area of openly folded Hurwitz Group and younger Kiyuk Group metasedimentary rocks. The structural style is similar in the Ennadai Block to northwest, which is considered to be the part of Hearne Province least affected by Trans-Hudson thermotectonism. The eastern boundary of the Mudjatik Domain dips steeply to southeast and is defined by a narrow, linear, without magnetic gradient that trends northeasterly. This pronounced geophysical lineament is traceable deviation from the Manitoba-Saskatchewan border northeasterly to the Nunavut border. A trough of low magnetic intensity, correlating with rocks of the Wollaston Domain, lies to south more rock types in the Mudjatik Domain. This boundary is considered to be structural origin and similar age Needle Falls Shear Zone (1855-1800 Ma; Stauffer and Lewry, 1993) that forms the eastern boundary of the observation that Wollaston Domain in Saskatchewan. This interpretation is consistent with metamorphic foliation in the quartz dioritic to granodioritic gneiss and migmatitic layering supracrustal inliers is openly folded about large, easterly trending axial planes, such as at Wolk Lake and Sector (Weber et al., 1975a). The folding the larger northeasterly trending structures on west side of Mudjatik-Wollaston domain boundary. dated at 1753 Ma (Loveridge et al., 1987). border, Manitoba the near Saskatchewan in begins The change in the character of Mudjatik Domain, which coincides with a change in the regional Bouguer gravity and aeromagnetic patterns. In Manitoba, Mudjatik Domain is characterized by greater negative values and marked a well defined northwesterly trending - 60 mGal contour interval. The aeromagnetic pattern suggests that the gneiss belt, characterized by flat-lying, lobes in Saskatchewan, forms an elongated dome that rises west of the Manitoba-Saskatchewan infrastructural border and plunges in a northeasterly direction west of Putahow Lake, Manitoba. Grey quartz dioritic and granodioritic gneiss pink mylonitic rocks of the Archean infrastructure as to referred Mudjatik Domain in Manitoba continue along strike to the northeast into Nunavut, where they are the Kasba gneisses. gniess has yielded bimodal ages of 3274 The textures of the deformed rocks in this shear zone indicate partial recrystallization under conditions Hudsonian metamorphism, indicating that deformation must have taken place prior to the amphibolite-facies metamorphism (Weber et al., 1975a). Low magnetic intensity Hurwitz Group metagreywacke (unit (Loveridge et al., 1988). The Archean rocks are structurally overlain by Hurwitz Group argillite (unit